<title>上白泽慧音</title><link href="http://hzoi.com/tomorrow.css" rel="stylesheet"><div class="ui existing segment"><pre><code><span class="pl-cp">#include</span><span class="pl-cpf">&lt;cstdio&gt;</span><span class="pl-cp"></span>
<span class="pl-cp">#include</span><span class="pl-cpf">&lt;algorithm&gt;</span><span class="pl-cp"></span>
<span class="pl-cp">#define MAXM 50005</span>
<span class="pl-cp">#define MAXN 10005</span>
<span class="pl-k">using</span> <span class="pl-k">namespace</span> <span class="pl-n">std</span><span class="pl-p">;</span>
<span class="pl-k">struct</span> <span class="pl-n">edge</span><span class="pl-p">{</span>
    <span class="pl-kt">int</span> <span class="pl-n">f</span><span class="pl-p">,</span><span class="pl-n">to</span><span class="pl-p">,</span><span class="pl-n">next</span><span class="pl-p">;</span>
    <span class="pl-n">edge</span><span class="pl-p">(){</span><span class="pl-n">to</span><span class="pl-o">=</span><span class="pl-n">next</span><span class="pl-o">=</span><span class="pl-mi">0</span><span class="pl-p">;}</span>
<span class="pl-p">}</span> <span class="pl-n">edges</span><span class="pl-p">[</span><span class="pl-n">MAXM</span><span class="pl-p">];</span>
<span class="pl-kt">int</span> <span class="pl-n">head</span><span class="pl-p">[</span><span class="pl-n">MAXM</span><span class="pl-p">],</span><span class="pl-n">tot</span><span class="pl-o">=</span><span class="pl-mi">1</span><span class="pl-p">;</span>
<span class="pl-kt">void</span> <span class="pl-nf">add</span><span class="pl-p">(</span><span class="pl-kt">int</span> <span class="pl-n">x</span><span class="pl-p">,</span><span class="pl-kt">int</span> <span class="pl-n">y</span><span class="pl-p">){</span>
    <span class="pl-n">edges</span><span class="pl-p">[</span><span class="pl-o">++</span><span class="pl-n">tot</span><span class="pl-p">].</span><span class="pl-n">to</span><span class="pl-o">=</span><span class="pl-n">y</span><span class="pl-p">;</span>
    <span class="pl-n">edges</span><span class="pl-p">[</span><span class="pl-n">tot</span><span class="pl-p">].</span><span class="pl-n">f</span><span class="pl-o">=</span><span class="pl-n">x</span><span class="pl-p">;</span>
    <span class="pl-n">edges</span><span class="pl-p">[</span><span class="pl-n">tot</span><span class="pl-p">].</span><span class="pl-n">next</span><span class="pl-o">=</span><span class="pl-n">head</span><span class="pl-p">[</span><span class="pl-n">x</span><span class="pl-p">];</span>
    <span class="pl-n">head</span><span class="pl-p">[</span><span class="pl-n">x</span><span class="pl-p">]</span><span class="pl-o">=</span><span class="pl-n">tot</span><span class="pl-p">;</span>
<span class="pl-p">}</span>
<span class="pl-kt">int</span> <span class="pl-n">n</span><span class="pl-p">,</span><span class="pl-n">m</span><span class="pl-p">,</span><span class="pl-n">x</span><span class="pl-p">,</span><span class="pl-n">y</span><span class="pl-p">,</span><span class="pl-n">z</span><span class="pl-p">;</span>
<span class="pl-kt">int</span> <span class="pl-n">dfn</span><span class="pl-p">[</span><span class="pl-n">MAXN</span><span class="pl-p">],</span><span class="pl-n">low</span><span class="pl-p">[</span><span class="pl-n">MAXN</span><span class="pl-p">],</span><span class="pl-n">cnt</span><span class="pl-p">,</span><span class="pl-n">dfs_clock</span><span class="pl-p">,</span><span class="pl-n">sta</span><span class="pl-p">[</span><span class="pl-n">MAXN</span><span class="pl-p">],</span><span class="pl-n">top</span><span class="pl-p">,</span><span class="pl-n">belong</span><span class="pl-p">[</span><span class="pl-n">MAXN</span><span class="pl-p">],</span><span class="pl-n">scc_cnt</span><span class="pl-p">,</span><span class="pl-n">siz</span><span class="pl-p">[</span><span class="pl-n">MAXN</span><span class="pl-p">];</span>
<span class="pl-kt">void</span> <span class="pl-nf">tarjan</span><span class="pl-p">(</span><span class="pl-kt">int</span> <span class="pl-n">u</span><span class="pl-p">){</span>
    
    <span class="pl-n">dfn</span><span class="pl-p">[</span><span class="pl-n">u</span><span class="pl-p">]</span> <span class="pl-o">=</span> <span class="pl-n">low</span><span class="pl-p">[</span><span class="pl-n">u</span><span class="pl-p">]</span> <span class="pl-o">=</span> <span class="pl-o">++</span> <span class="pl-n">dfs_clock</span><span class="pl-p">;</span>
    <span class="pl-n">sta</span><span class="pl-p">[</span><span class="pl-o">++</span><span class="pl-n">top</span><span class="pl-p">]</span> <span class="pl-o">=</span> <span class="pl-n">u</span><span class="pl-p">;</span> 
    
    <span class="pl-k">for</span><span class="pl-p">(</span><span class="pl-kt">int</span> <span class="pl-n">x</span> <span class="pl-o">=</span> <span class="pl-n">head</span><span class="pl-p">[</span><span class="pl-n">u</span><span class="pl-p">];</span><span class="pl-n">x</span><span class="pl-p">;</span><span class="pl-n">x</span><span class="pl-o">=</span><span class="pl-n">edges</span><span class="pl-p">[</span><span class="pl-n">x</span><span class="pl-p">].</span><span class="pl-n">next</span><span class="pl-p">){</span>
        <span class="pl-kt">int</span> <span class="pl-n">v</span><span class="pl-o">=</span><span class="pl-n">edges</span><span class="pl-p">[</span><span class="pl-n">x</span><span class="pl-p">].</span><span class="pl-n">to</span><span class="pl-p">;</span>
        
        <span class="pl-k">if</span><span class="pl-p">(</span><span class="pl-o">!</span><span class="pl-n">dfn</span><span class="pl-p">[</span><span class="pl-n">v</span><span class="pl-p">]){</span>
            <span class="pl-n">tarjan</span><span class="pl-p">(</span><span class="pl-n">v</span><span class="pl-p">);</span>
            <span class="pl-n">low</span><span class="pl-p">[</span><span class="pl-n">u</span><span class="pl-p">]</span> <span class="pl-o">=</span> <span class="pl-n">min</span><span class="pl-p">(</span><span class="pl-n">low</span><span class="pl-p">[</span><span class="pl-n">u</span><span class="pl-p">],</span> <span class="pl-n">low</span><span class="pl-p">[</span><span class="pl-n">v</span><span class="pl-p">]);</span>
        <span class="pl-p">}</span><span class="pl-k">else</span> <span class="pl-k">if</span><span class="pl-p">(</span><span class="pl-o">!</span><span class="pl-n">belong</span><span class="pl-p">[</span><span class="pl-n">v</span><span class="pl-p">])</span> <span class="pl-n">low</span><span class="pl-p">[</span><span class="pl-n">u</span><span class="pl-p">]</span> <span class="pl-o">=</span> <span class="pl-n">min</span><span class="pl-p">(</span><span class="pl-n">low</span><span class="pl-p">[</span><span class="pl-n">u</span><span class="pl-p">],</span><span class="pl-n">dfn</span><span class="pl-p">[</span><span class="pl-n">v</span><span class="pl-p">]);</span>
    <span class="pl-p">}</span>
    <span class="pl-k">if</span><span class="pl-p">(</span><span class="pl-n">dfn</span><span class="pl-p">[</span><span class="pl-n">u</span><span class="pl-p">]</span> <span class="pl-o">==</span> <span class="pl-n">low</span><span class="pl-p">[</span><span class="pl-n">u</span><span class="pl-p">]){</span>
        <span class="pl-n">scc_cnt</span><span class="pl-o">++</span><span class="pl-p">;</span>
        <span class="pl-k">while</span><span class="pl-p">(</span><span class="pl-mi">1</span><span class="pl-p">){</span>
            <span class="pl-kt">int</span> <span class="pl-n">x</span> <span class="pl-o">=</span> <span class="pl-n">sta</span><span class="pl-p">[</span><span class="pl-n">top</span><span class="pl-o">--</span><span class="pl-p">];</span> 
            <span class="pl-n">belong</span><span class="pl-p">[</span><span class="pl-n">x</span><span class="pl-p">]</span> <span class="pl-o">=</span> <span class="pl-n">scc_cnt</span><span class="pl-p">;</span> 
            <span class="pl-n">siz</span><span class="pl-p">[</span><span class="pl-n">scc_cnt</span><span class="pl-p">]</span> <span class="pl-o">++</span> <span class="pl-p">;</span> 
            <span class="pl-k">if</span><span class="pl-p">(</span><span class="pl-n">x</span> <span class="pl-o">==</span> <span class="pl-n">u</span><span class="pl-p">)</span> <span class="pl-k">break</span><span class="pl-p">;</span> 
        <span class="pl-p">}</span>
    <span class="pl-p">}</span>
<span class="pl-p">}</span>
<span class="pl-kt">int</span> <span class="pl-n">out</span><span class="pl-p">[</span><span class="pl-n">MAXN</span><span class="pl-p">];</span>
<span class="pl-kt">int</span> <span class="pl-nf">main</span><span class="pl-p">(){</span>
    <span class="pl-n">scanf</span><span class="pl-p">(</span><span class="pl-s">&quot;%d%d&quot;</span><span class="pl-p">,</span><span class="pl-o">&amp;</span><span class="pl-n">n</span><span class="pl-p">,</span><span class="pl-o">&amp;</span><span class="pl-n">m</span><span class="pl-p">);</span>
    <span class="pl-k">for</span><span class="pl-p">(</span><span class="pl-kt">int</span> <span class="pl-n">i</span><span class="pl-o">=</span><span class="pl-mi">1</span><span class="pl-p">;</span><span class="pl-n">i</span><span class="pl-o">&lt;=</span><span class="pl-n">m</span><span class="pl-p">;</span><span class="pl-n">i</span><span class="pl-o">++</span><span class="pl-p">){</span>
        <span class="pl-n">scanf</span><span class="pl-p">(</span><span class="pl-s">&quot;%d%d%d&quot;</span><span class="pl-p">,</span><span class="pl-o">&amp;</span><span class="pl-n">x</span><span class="pl-p">,</span><span class="pl-o">&amp;</span><span class="pl-n">y</span><span class="pl-p">,</span><span class="pl-o">&amp;</span><span class="pl-n">z</span><span class="pl-p">);</span>
        <span class="pl-n">add</span><span class="pl-p">(</span><span class="pl-n">x</span><span class="pl-p">,</span><span class="pl-n">y</span><span class="pl-p">);</span>
        <span class="pl-k">if</span><span class="pl-p">(</span><span class="pl-n">z</span><span class="pl-o">==</span><span class="pl-mi">2</span><span class="pl-p">)</span><span class="pl-n">add</span><span class="pl-p">(</span><span class="pl-n">y</span><span class="pl-p">,</span><span class="pl-n">x</span><span class="pl-p">);</span>
    <span class="pl-p">}</span>
    <span class="pl-k">for</span><span class="pl-p">(</span><span class="pl-kt">int</span> <span class="pl-n">i</span><span class="pl-o">=</span><span class="pl-mi">1</span><span class="pl-p">;</span><span class="pl-n">i</span><span class="pl-o">&lt;=</span><span class="pl-n">n</span><span class="pl-p">;</span><span class="pl-n">i</span><span class="pl-o">++</span><span class="pl-p">)</span><span class="pl-k">if</span><span class="pl-p">(</span><span class="pl-o">!</span><span class="pl-n">dfn</span><span class="pl-p">[</span><span class="pl-n">i</span><span class="pl-p">])</span><span class="pl-n">tarjan</span><span class="pl-p">(</span><span class="pl-n">i</span><span class="pl-p">);</span>
    
    <span class="pl-kt">int</span> <span class="pl-n">mi</span><span class="pl-o">=</span><span class="pl-n">max_element</span><span class="pl-p">(</span><span class="pl-n">siz</span><span class="pl-o">+</span><span class="pl-mi">1</span><span class="pl-p">,</span><span class="pl-n">siz</span><span class="pl-o">+</span><span class="pl-n">scc_cnt</span><span class="pl-o">+</span><span class="pl-mi">1</span><span class="pl-p">)</span><span class="pl-o">-</span><span class="pl-n">siz</span><span class="pl-p">;</span>
    <span class="pl-n">printf</span><span class="pl-p">(</span><span class="pl-s">&quot;%d</span><span class="pl-se">\n</span><span class="pl-s">&quot;</span><span class="pl-p">,</span><span class="pl-n">siz</span><span class="pl-p">[</span><span class="pl-n">mi</span><span class="pl-p">]);</span>
    <span class="pl-k">for</span><span class="pl-p">(</span><span class="pl-kt">int</span> <span class="pl-n">i</span><span class="pl-o">=</span><span class="pl-mi">1</span><span class="pl-p">;</span><span class="pl-n">i</span><span class="pl-o">&lt;=</span><span class="pl-n">n</span><span class="pl-p">;</span><span class="pl-n">i</span><span class="pl-o">++</span><span class="pl-p">){</span>
        <span class="pl-k">if</span><span class="pl-p">(</span><span class="pl-n">belong</span><span class="pl-p">[</span><span class="pl-n">i</span><span class="pl-p">]</span><span class="pl-o">==</span><span class="pl-n">mi</span><span class="pl-p">){</span>
            <span class="pl-n">printf</span><span class="pl-p">(</span><span class="pl-s">&quot;%d &quot;</span><span class="pl-p">,</span><span class="pl-n">i</span><span class="pl-p">);</span>
        <span class="pl-p">}</span>
    <span class="pl-p">}</span>
    <span class="pl-k">return</span> <span class="pl-mi">0</span><span class="pl-p">;</span>
<span class="pl-p">}</span>
</cpde></pre></div>